He studied law at the University of Malta where he obtained the Diploma of Notary Public in 1974.

In 1975 he graduated Doctor of Laws and practised law for a number of years since 1976. He has also served as legal adviser to companies and other corporate bodies in Malta and abroad. He became lecturer in 1979 and senior lecturer in 1988 at the University of Malta, lecturing in Company Law, Industrial Law and European Law. He has also lectured at the Malta Institute of Accountants and at the Institute of Bankers.

In 1980 he participated in an International Teachers Programme at the Manchester University Business School and between 1987 and 1988 he pursued postgraduate studies in European Law at the University College of Wales.

In 1988 he graduated Master in European Law after successfully submitting his thesis entitled "Company Law Harmonisation in the EEC - Suggested Changes in Maltese Law". He was the main author and was responsible for the drafting of The Companies Act, 1995.

Between 1989 and 1995 Dr. Borg was adviser on European Union matters to the Minister of Foreign Affairs. During these years he set up and headed the Directorate for EU matters in the Ministry of Foreign Affairs and also prepared and drew up the "Report Regarding Malta’s Membership of the European Community" published by the Maltese Government in March 1990.

Between 1989 and 1992 Dr. Borg became a member of the Board of Governors of the Malta International Business Authority and between 1992 and 1995 he was a Director of the Board of Directors of the Central Bank of Malta.

Dr. Borg was first elected to the House of Representatives in the interests of the Nationalist Party in 1995 and was re-elected to the House in the General Elections of 1996.

Between 1996 and 1998 he was Shadow Minister responsible for Industry and for the impact of EU policies on Malta. During the same period he was a Member of the Foreign Affairs Committee of the House of Representatives and of the EU-Malta Joint Parliamentary Committee. In 1997 he was elected International Secretary of the Nationalist Party.

Dr. Borg was elected for the third time to the House of Representatives at the General Elections of 1998, and following the Nationalist Party victory he was appointed Parliamentary Secretary in the Ministry of Foreign Affairs, member of the Foreign Affairs Committee of the House of Representatives and First Vice-Chairman of the EU-Malta Joint Parliamentary Committee

In March, 1999 Dr. Joseph Borg was appointed Minister of Foreign Affairs of Malta.

Dr. Joseph Borg is married to Isabelle née Agius and they have two children, Joseph and Maria Clara.